Stocks are flashing a buy sign: Technician

It's the investment equivalent of Pavlov's dog. Each time the S&P 500 has touched its 200-day moving average, a sharp rally has soon followed.

And with the recent selloff, the S&P 500 is hovering just above that key technical level, and that has one top technician banging the table on stocks.

"Take advantage of the fear that's out there right now," said Rich Ross, a technician at Evercore ISI, on Monday's "Fast Money."

Ross noted that since 2011, the market has touched its 200-day moving average three times and each time the market has waged a significant rally. The first time was in 2012 which led to a 15-percent rally in stocks in the following three months and again toward the end of that year, which sparked a nearly 50-percent rally in stocks over the next 10 months. The third time was in October of last year, which has led stocks to another 14 percent in gains since then.

"There is absolutely no subjectivity in moving averages like the 200-day moving average; in contrast to trend lines and horizontal lines of support and resistance, the 200-day moving average is the same for everyone."

"Three big rallies after the dip below [the 200-day moving average], and I think you're going to see history repeat itself," said Ross.